Coerce operations in match? to booleans

The compiler is merging null-doubles with these matchers.
Methods that normally return a boolean instead return the instance 
(self).
This causes a return type-mismatch.
There should be a better alternative to this.

src/spectator/matchers/case_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value === actual.value
+      !!(expected.value === actual.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/collection_matcher.cr

@@ -14,7 +14,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value.includes?(actual.value)
+      !!expected.value.includes?(actual.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/contain_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value.all? do |item|
+      !!expected.value.all? do |item|
         actual.value.includes?(item)
       end
     end

src/spectator/matchers/empty_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value.empty?
+      !!actual.value.empty?
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/equality_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value == actual.value
+      !!(expected.value == actual.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/greater_than_equal_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value >= expected.value
+      !!(actual.value >= expected.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/greater_than_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value > expected.value
+      !!(actual.value > expected.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/have_key_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value.has_key?(expected.value)
+      !!actual.value.has_key?(expected.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/have_matcher.cr

@@ -23,17 +23,17 @@ module Spectator::Matchers
 
     # Checks if a `String` matches the expected values.
     # The `includes?` method is used for this check.
-    private def match_string?(value)
-      expected.value.all? do |item|
+    private def match_string?(value) : Bool
+      !!expected.value.all? do |item|
         value.includes?(item)
       end
     end
 
     # Checks if an `Enumerable` matches the expected values.
     # The `===` operator is used on every item.
-    private def match_enumerable?(value)
+    private def match_enumerable?(value) : Bool
       array = value.to_a
-      expected.value.all? do |item|
+      !!expected.value.all? do |item|
         array.any? do |element|
           item === element
         end

src/spectator/matchers/have_value_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value.has_value?(expected.value)
+      !!actual.value.has_value?(expected.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/inequality_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value != actual.value
+      !!(expected.value != actual.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/less_than_equal_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value <= expected.value
+      !!(actual.value <= expected.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/less_than_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value < expected.value
+      !!(actual.value < expected.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/nil_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value.nil?
+      !!actual.value.nil?
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/range_matcher.cr

@@ -27,7 +27,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value.includes?(actual.value)
+      !!expected.value.includes?(actual.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/reference_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value.same?(actual.value)
+      !!expected.value.same?(actual.value)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/size_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value == actual.value.size
+      !!(expected.value == actual.value.size)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/size_of_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      expected.value.size == actual.value.size
+      !!(expected.value.size == actual.value.size)
     end
 
     # Message displayed when the matcher isn't satisifed.

src/spectator/matchers/type_matcher.cr

@@ -13,7 +13,7 @@ module Spectator::Matchers
 
     # Checks whether the matcher is satisifed with the expression given to it.
     private def match?(actual : TestExpression(T)) : Bool forall T
-      actual.value.is_a?(Expected)
+      !!actual.value.is_a?(Expected)
     end
 
     # Message displayed when the matcher isn't satisifed.